This invention relates to a mounting device for connecting the accessories of endoscope oculars, such as a camera and a teaching scope, to the oculars of an endoscope.
Accessories such as a camera and a teaching scope are connected to the ocular of an endoscope by a bayonet device or a friction engagement device.
When the bayonet device is used, the accessory is fixed to the ocular. Thus, if the endoscope is rotated to find out the portion of a coeliac cavity to be observed, the accessory is also rotated together with the endoscope. It gives inconvenience to an operator of the endoscope. When the teaching scope is used, it has the drawback that the image guide bundle is twisted by the rotation.
On the other hand, when the friction engagement device is used, the accessory can freely rotate relative to the endoscope. Suppose that camera is connected to the endoscope with its distal end inserted in a body cavity. But the friction engagement device has the drawback that, if the operator rotates the camera in an attempt to rotate the endoscope thereby to search the portion of the coeliac cavity to be observed the endoscope will not rotate because its distal end portion is held immovable by the friction between it and the body cavity wall, and only the camera if rotated. To rotate the endoscope together with the camera, the operator must hold the camera by one hand and the endoscope by the other hand. This adds to the cumbersome operation of the photographing.
In recent years the endoscopes have been used more often in order to carry out a medical treatment or a small operation in a body cavity. In many cases the operator has to manipulate an endoscope by one hand and handle an medical instrument by the other hand. During examination of the abdominal cavity, for example, the operator manipulates the endoscope by one hand while he operates a probe by the other hand to move an organ in the abdominal cavity. When the photographs are taken while the endoscope is rotated, the camera is also rotated. Thus, it is inconvenient for the operator to work the camera.
As mentioned above, only two types of accessory mounting devices are known, one type securing an accessory immovably to an endoscope and the other type connecting an accessory rotatably to an endoscope. Both types have the above-mentioned drawbacks. In many cases it is desired that an accessory be sometimes fixed to an endoscope and be sometimes rotatably connected to the endoscope. Such being the case, there has been a strong demand for mounting devices which permit an easy and correct operation of an endoscope and its accessories.